[Formulajones]

I've had very similar results over the last 35 years of trying things at the track and on the street with only minor differences.

With the stock large cannister GM mechanical pump and stock fuel lines I've gone as quick as 12.50's and 60's at 108 mph in a 4100 lbs. car. It was at that point I hit a wall with that car, no matter what changed it ran nearly the same.
I'm at that same point with the Firebird currently and based off what I've experienced it won't go any faster without some major fuel system changes.

On the other car I did go through all the changes Cliff mentioned with some variances here and there. For years I settled on ditching the mechanical pump completely and running a Mallory 140 back at the tank, still using the stock lines and stock pickup in the tank. I pushed the car to 11.40's at 118 mph with that deal. My problem with it was the need to rebuild that pump with new brushes about every 3-4 years. Quite frankly I got sick and tired of it and the fact that I didn't feel I could trust it for any real distance. Inline pumps have always been that way from my experiences.

That's when I broke down and did the Tanks Inc setup, a 450 LPH pump in the tank, and ran 1/2" lines to and from with a full length return. Been that way for a bunch of years now with no issues to date, and will support all the HP I'll ever throw at it. Ever since every car I setup now, whether a stout street car or strip only, it just gets a Tank Inc setup right from the start so I don't have to go back and monkey with that deal anymore from that point forward no matter what's done to the engine.

I never really got into the whole "add a pusher pump" deal while running a mechanical. I just never found a need to. I don't understand how sitting for periods of time causes such an issue that the car won't start without a pusher pump. I still run several cars here with stock mechanical pumps. Some do sit for periods of time and I've never found them difficult to start. They don't crank for any length of time that I'd consider abnormal, maybe 4-5 seconds. Just not a big deal.
Both of our dailys still run stock mechanical pumps as well and it just seems to work fine. None of these stock mechanical pump cars make more than about 400hp either so the stock pumps supply fuel to these cars just fine at that power level. Like I said I've gone 12's with stock fuel systems with no need for an added pusher pump, so unless I start adding more HP, those particular cars will stay with the stock pump setups.